Effect of coenzyme Q10 supplementation on heart failure: a meta-analysis

Background: Coenzyme Q(10) (CoQ(10); also called ubiquinone) is an antioxidant that has been postulated to improve functional status in congestive heart failure (CHF). Several randomized controlled trials have examined the effects of CoQ(10) on CHF with inconclusive results. Objective: The objective of this meta-analysis was to evaluate the impact of CoQ(10) supplementation on the ejection fraction (EF) and New York Heart Association (NYHA) functional classification in patients with CHF. Design: A systematic review of the literature was conducted by using databases including MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, and manual examination of references from selected studies. Studies included were randomized controlled trials of CoQ(10) supplementation that reported the EF or NYHA functional class as a primary outcome. Information on participant characteristics, trial design and duration, treatment, dose, control, EF, and NYHA classification were extracted by using a standardized protocol. Results: Supplementation with CoQ(10) resulted in a pooled mean net change of 3.67% (95% CI: 1.60%, 5.74%) in the EF and -0.30 (95% CI: -0.66, 0.06) in the NYHA functional class. Subgroup analyses showed significant improvement in EF for crossover trials, trials with treatment duration <= 12 wk in length, studies published before 1994, and studies with a dose <= 100 mg CoQ(10)/d and in patients with less severe CHF. These subgroup analyses should be interpreted cautiously because of the small number of studies and patients included in each subgroup. Conclusions: Pooled analyses of available randomized controlled trials suggest that CoQ(10) may improve the EF in patients with CHF. Additional well-designed studies that include more diverse populations are needed. Am J Clin Nutr 2013;97:268-75.